/*
 * Copyright 2021 Realm Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.realm;

/**
 * {@link MapChangeListener} can be registered with a {@link RealmMap} to receive a notification
 * with a {@link MapChangeSet} to describe the details of what have been changed in the map since
 * last time.
 * <p>
 * Realm instances on a thread without an {@link android.os.Looper} cannot register a
 * {@link MapChangeListener}.
 * <p>
 *
 * @param <K> the type of the keys stored in the map
 * @param <V> the type of the values stored in the map
 * @see RealmMap#addChangeListener(MapChangeListener)
 */
public interface MapChangeListener<K, V> {

    /**
     * This will be called when the async query is finished the first time or the collection of objects has changed.
     *
     * @param map     the map this listener is registered to.
     * @param changes object with information about the change.
     */
    void onChange(RealmMap<K, V> map, MapChangeSet<K> changes);
}
